Container preform



FIG. 1 is a top perspective view of a container preform showing the claimed design;

FIG. 2 is a bottom perspective view thereof;

FIG. 3 is a front view thereof;

FIG. 4 is a rear view thereof;

FIG. 5 is a left side view thereof;

FIG. 6 is a right side view thereof;

FIG. 7 is a top view thereof;

FIG. 8 is a bottom view thereof; and

FIG. 9 is a cross-sectional view thereof, taken along line 9-9 of FIG. 7 . 

CLAIM The ornamental design for a container preform as shown and described. 